Firebase访问Swift 3中的快照值错误 [英] Firebase Accessing Snapshot Value Error in Swift 3

问题描述

我最近升级到swift 3，并且在尝试从快照观察事件值访问某些事物时遇到错误。

我的代码：

$ b $ pre $ ref $ c $ ref ref.child（users）。child（userID！）。observeSingleEvent（of：.value，with：{（snapshot）in

let username = snapshot.value！[fullName] as！String
let homeAddress = snapshot.value！[homeAddress] as！[Double]
let email = snapshot.value！[email] as！String
}

上面列出的三个变量和状态：

类型'任何'没有下标成员

任何帮助将是非常感谢

解决方案

我认为你可能需要投射你的 snapshot.value 作为 NSDictionary 。

  ref.child（users ）.child（userID！）。observeSingleEvent（：.value，其中：{（snapshot）in 
 
 let value = snapshot .value as？NSDictionary 
 
 let username = value？[fullName] as？字符串？ 
让homeAddress = value？[homeAddress]为？ [双]？ [] 
让email = value？[email]为？字符串？ 
 
} 
  

您可以参阅firebase文档： a href =https://firebase.google.com/docs/database/ios/read-and-write =noreferrer> https://firebase.google.com/docs/database/ios/read-并写入

I recently upgraded to swift 3 and have been getting an error when trying to access certain things from a snapshot observe event value.

My code:

ref.child("users").child(userID!).observeSingleEvent(of: .value, with: { (snapshot) in

    let username = snapshot.value!["fullName"] as! String
    let homeAddress = snapshot.value!["homeAddress"] as! [Double]
    let email = snapshot.value!["email"] as! String
}

The error is around the three variables stated above and states:

Type 'Any' has no subscript members

Any help would be much appreciated

解决方案

I think that you probably need to cast your snapshot.value as a NSDictionary.

ref.child("users").child(userID!).observeSingleEvent(of: .value, with: { (snapshot) in

    let value = snapshot.value as? NSDictionary

    let username = value?["fullName"] as? String ?? ""
    let homeAddress = value?["homeAddress"] as? [Double] ?? []
    let email = value?["email"] as? String ?? ""

}

You can take a look on firebase documentation: https://firebase.google.com/docs/database/ios/read-and-write

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